What made you decide to invest your time in fitness/diet?

I am just curious to see where everyone is coming from.

For me, I was always a chubby guy. I was chubby as a kid and a teen. I got teased for it on and off. I was never super overweight but because I have always had a small frame and a tall lanky build, the way my body carried fat just looked bad. I woke up on my 25th birthday and decided to change it. This was a month ago. I started losing some weight already but I want to gain muscle as well. So basically for me, I just got sick of looking bad. Also, feeling bad. I know it was down to diet and just being inactive. I play tons of video games and don't so much else. Even whilst working, I am sitting all day (I do security).